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Ned Potter is the science correspondent for ABC's "World News with Charles Gibson." He has reported on such topics as space exploration, the human genome and climate change.
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Maybe the Sky is NOT Falling
January 28, 2008 11:23 AM
So there's an American spy satellite -- its actual mission, orbit and size not made public -- which has lost power and, like all other objects in low Earth orbit, is gradually losing altitude because of friction with the tenuous atmosphere that exists even hundreds of miles up.
"Disabled Spy Satellite Threatens Earth," said many headlines, including our own.
"Duck!" joked an e-mail to me on Saturday.
We could fully understand if you wanted to duck, what with all the talk of hydrazine fuel and chunks of beryllium raining to Earth. Only, only....
It's not quite like that. Here's what we can say:
First of all, the chance of harm to human beings is very small, if only because 70 percent of the planet's surface is water, and most of the land is mountain, desert, farmland or frozen tundra. We earthlings crowd onto only a few percent of the space down here.
John Pike's GlobalSecurity.org suggests the satellite is labeled NROL-21, launched in December 2006 from Vandenberg Air Force Base (which would most likely put it in an orbit that takes it over both poles). Pike's group reports it's a radar imaging satellite with large solar panels and a dish antenna. If Pike is correct and it was launched by a Delta II rocket, it is not very massive, but sturdier parts could conceivably make it to the ground in an uncontrolled re-entry.
The vast majority of satellites are completely vaporized as they re-enter the atmosphere.
There are hundreds of satellites that have been large enough that parts survived descent, but nobody -- not a single person that we know of --has been hurt in the 50 years since Sputnik 1. There was a woman named Lottie Williams, in Tulsa, Okla., who felt a soft tap on the shoulder when she was out walking one night; NASA decided the burnt piece of debris she found on the ground was lightweight insulation from a rocket nozzle. We interviewed her in 1999 and she said she was disappointed. (I checked back recently and was told she is still unique.)
Most likely, today's errant satellite is large enough that the government fears embarrassment, or the compromising of secrets, if parts of it come down in the wrong country. That provoked some meetings last week, which probably provoked a leak on Saturday.
"Numerous satellites over the years have come out of orbit and fallen harmlessly. We are looking at potential options to mitigate any possible damage this satellite may cause," said Gordon Johndroe of the National Security Council.
So there's the potential for a bit of intrigue. But, no, you don't have to duck.
(Satellite concept sketch from globalsecurity.org.)
==========================
Update, added Monday afternoon: for more information on the toxicity of hydrazine fuels, see what the CDC has posted HERE. More on beryllium is HERE.
Meanwhile, the BBC has its own day-after story by Kathryn Westcott, which makes me feel un-original: "Why the spy satellite won't fall on your head." The subtitle: "This is not Armageddon: stand down, Bruce Willis, we don't need you!" Find it HERE.
January 28, 2008 | Permalink | Share | User Comments (15)
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This news item reminds me of the great alarm shown in the late 1970's when Skylab's orbit began to decline with the eventual result of its few remains crashing to earth. The difference here, however, is that this is a "spy satellite" with who knows how much government information on board. Perhaps the DoD is warning us because there's something potentially embarassing in the satellite, like a top secret recipe for Mai Tais.
Posted by: chuck | Jan 28, 2008 12:19:05 PM
I dunno. Chicken Little just might be right. The stated mass of that thing is on the order of 10 tons. Trying to shed that much mass may be too much even for our thick atmosphere. I shall keep my eyes peeled for suspicious trails in the sky. I mean, after all, Chicken Little has at least as much perspicacity as the Government. Or is it the other way 'round?
Posted by: Andy | Jan 28, 2008 12:29:46 PM
What is a bigger question is what caused a new satellite go belly up so quicky.
Is it true china is picking off all our military satellites and we cannot do anything about it ?
Posted by: JR | Jan 28, 2008 12:38:57 PM
Awesome sketch of the spy satellite- eraser and grid marks included!!!
Posted by: ERIN | Jan 28, 2008 1:01:37 PM
So Ned... what happens to "hydrazine fuel and chunks of beryllium" when it is vaporized? Does it just "go away" ? Or does it just become a vapor that will spread out in our already ailing atmosphere? What happens when these things fall into our oceans? Out of sight out of mind? Perhaps this non-nonchalant attitude about things such as this is what has tossed our fragile eco-system into the crapper... ya think?
Posted by: RW | Jan 28, 2008 1:57:26 PM
Maybe Osama Bin Laden is in the satellite
Posted by: pete | Jan 28, 2008 1:59:47 PM
Note from Ned--
RW has raised the question about the toxics that may be on board the satellite. I've added links to the bottom of the post.
Posted by: Ned Potter | Jan 28, 2008 2:13:11 PM
Skylab weighed on the order of 78 tons. It reentered with no damage (on Earth) to speak of: I think one cow was killed in the Australian outback. Personally, I can't see how anything but a few small bits, if anything, of this satellite could make it to Earth.
Posted by: Robert | Jan 28, 2008 2:31:06 PM
The satellite was launched on a Delta II rocket. The max payload is only about 3-4 tons not 10.
The satellite failed shortly after launch. China is not picking off our satellites.
The amount of propellant and other toxic materials on board the satellite is minuscule compared to the amount of other pollutants that get dumped into the atmosphere every second.
Posted by: Opie | Jan 28, 2008 3:15:14 PM
By the time you see the contrail, the pieces have already gone by and are in the next state. And that is if there are no clouds. Well, if the thing is actually going to rain some pieces on Earth's surface, I wish they could hit somebody convenient... like that Halliburton guy, maybe, or Osama.
Posted by: Jordan | Jan 28, 2008 3:20:40 PM
The junk they send up, eventually has to come raining down. As if we don't have an overload of garbage now. I think we should have some fun with this one........where in the world will it land...........think you have ESP.....take a guess.
I say........New York
Posted by: Ann Graywolf | Jan 28, 2008 8:38:12 PM
I'm wondering if this is what we saw from an island in Glover's Reef, Belize. We were looking at phosphorescents in the water, and at the exact moment that my friend said “OK, turn on your lamp”, the water lit up in a way that we knew was not my headlamp, and we both looked up into the night sky. What we saw seemed to be a meteorite or asteroid or comet with a double tail! It was about 8 pm local time on Friday night, January 25th. Since coming back to civilization with access to the web, I found that a huge asteroid adorned the night sky that night at 13:52 GMT, but further research showed that what we saw could not have been asteroid TU-24, which some NASA source said would "reach an approximate apparent magnitude 10.3 on Jan. 29-30 before quickly becoming fainter as it moves farther from Earth. On that night, the asteroid will be observable in dark and clear skies through amateur telescopes with apertures of at least 7.6 centimeters (three inches)." So, now I'm wondering if we saw this falling satellite?
Posted by: Mark Berg | Jan 29, 2008 8:05:47 AM
It's all about the lenses, sensors and the software running/filtering all the info the satellite gathers. We don't want the "others" to know what we know, or can possibly know.
The fuel issue or the falling pieces--can you say smokescreen?
Posted by: Roger | Feb 15, 2008 4:06:40 PM
why was this spy satilite not equiped with a self`destruct device onboard so it could be destroyed if it malfuctioned??
Posted by: chikinda | Feb 15, 2008 5:10:19 PM
how is the sattellite gonna blow up if there is no oxygen in space this ain't Hollywood
Posted by: josh schumer | Feb 17, 2008 3:40:15 PM
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